Animate the background color
<UserControl x:Class='SilverlightApplication3.MainPage' xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation' xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml' xmlns:d='http://schemas.microsoft.com/expression/blend/2008' xmlns:mc='http://schemas.openxmlformats.org/markup-compatibility/2006' mc:Ignorable='d' d:DesignWidth='640' d:DesignHeight='480'> <UserControl.Triggers> <EventTrigger RoutedEvent="Window.Loaded"> <BeginStoryboard> <Storyboard AutoReverse="True" RepeatBehavior="Forever"> <ColorAnimation Storyboard.TargetProperty="Background.Color" To="White" /> <ColorAnimation Storyboard.TargetName="rect" Storyboard.TargetProperty="(Shape.Fill).(SolidColorBrush.Color)" To="Firebrick" /> </Storyboard> </BeginStoryboard> </EventTrigger> </UserControl.Triggers> <Rectangle x:Name="rect" Width="100" Height="100" Fill="WhiteSmoke" /> </UserControl>